Introduction

Parasites are the major cause of ill health and early death in the world today. Malaria, sleeping sickness, amoebic dysentery, and hookworm infection are examples of commonplace parasitic diseases that are endemic in most parts of the world (see Health, Healing, and Disease). They were significant threats in prehistory, especially in cultures whose social complexity outstripped the development of effective sanitation, hygiene, and germ theory awareness.

Parasites are organisms that live in or on other organisms called hosts. Parasites derive sustenance and shelter from their hosts and carry out reproduction in host tissues and structures. There is a wide amount of taxonomic diversity among parasites. They range from single-celled protozoa, such as amoeba, to mul-ticelled arthropods such as fleas. Strictly defined, parasites do not include bacteria and viruses. However, some epidemiologists refer to bacteria and viruses as microparasites. There are two general types of parasites: ectoparasites such as lice and endoparasites such as intestinal worms.

All types of parasites can be found in archaeological sites. Protozoa can be identified by traces of antigens and also by certain gross pathology they left in their mummified hosts. Helminths are parasitic worms including nematode roundworms, cestode tapeworms, trematode flukes, and acanthocephalan thorny-headed worms. Helminth eggs from some species are laid in thousands within their hosts. Helminth eggs from humans and domestic animals contaminated ancient villages. The eggs are very durable and are easily retrieved from archaeological sediments, coprolites, and mummies. Fleas and lice can be found on mummies and also in archaeological sediments. Lice are especially important in mummy studies because the eggs are cemented on hair shafts. Therefore, examination of scalps from mummies provides a method of quantifying infestations between individuals and sites.

The discipline that focuses on the relationships between behavior, environment, and parasite infection is archaeoparasitology. This field developed from the need for a fine-tuned analysis of prehistoric ecological and behavioral conditions to assess the factors that affected disease. Archaeoparasitology depends on archaeological information regarding community size, trade patterns, water sources, subsistence practices, social stratification, environment, medicine use, and many other lines of modern archaeological investigation. It also depends on biological understanding of complex parasite life cycles and other dimensions of parasite ecology. When broadly applied, arch-aeoparasitology defines the rise in parasitic disease associated with the development of complex societies and changes in subsistence strategies. In a more restricted application, archaeoparasitology sheds light on the health impact of urbanization and empire expansion. When tightly applied to a single burial or mummy, archaeoparasitology shows how habits promote disease on an individual basis.